.main{
	margin: 60px 0 20px;
	min-height: 600px;
	.tg{
		height: 400px;
		background: #f2f2f2;
	}
	.kb{
		margin-top: 20px;
		ul{
			width: 1250px;
			li{
			   width: 340px;
			   height: 190px;
			   float: left;
			   margin-right: 30px;
			   box-shadow: 0 0 2px rgba(#ddd,0.6);
			   border-radius: 5px;
			   overflow: hidden;
			   img{
			   width: 100%;
			   }
			}
		}
	}
}